package com.qianlima.upload.infrastructure.utils;

import org.springframework.web.multipart.MultipartFile;

import java.io.*;
import java.util.Base64;

/**
 * @description: base64转MultipartFile
 * @author：allms
 * @date: 2023/3/22 16:04
 */
public class Base64ToMultipartFile implements MultipartFile {

    private final byte[] imgContent;
    private final String header;

    public Base64ToMultipartFile(byte[] imgContent, String header) {
        this.imgContent = imgContent;
        this.header = header.split(";")[0];
    }

    public static MultipartFile base64ToMultipart(String base64) {
        String[] baseStrs = base64.split(",");
        byte[] decode;
        decode = Base64.getDecoder().decode(baseStrs[1]);


        for (int i = 0; i < decode.length; ++i) {
            if (decode[i] < 0) {
                decode[i] += 256;
            }
        }
        return new Base64ToMultipartFile(decode, baseStrs[0]);
    }

    @Override
    public String getName() {
        // TODO - implementation depends on your requirements
        return System.currentTimeMillis() + Math.random() + "." + header.split("/")[1];
    }

    @Override
    public String getOriginalFilename() {
        // TODO - implementation depends on your requirements
        return System.currentTimeMillis() + 0 + "." + header.split("/")[1];
    }

    @Override
    public String getContentType() {
        // TODO - implementation depends on your requirements
        return header.split(":")[1];
    }

    @Override
    public boolean isEmpty() {
        return imgContent == null || imgContent.length == 0;
    }

    @Override
    public long getSize() {
        return imgContent.length;
    }

    @Override
    public byte[] getBytes() {
        return imgContent;
    }

    @Override
    public InputStream getInputStream() {
        return new ByteArrayInputStream(imgContent);
    }

    @Override
    public void transferTo(File dest) throws IOException, IllegalStateException {
        new FileOutputStream(dest).write(imgContent);
    }
}
